Airworthiness Directives; McDonnell Douglas Model DC-9-81, -82, -83, and -87 Series Airplanes, and Model MD-88 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9-81, -82, -83, and - 87 series airplanes, and Model MD-88 airplanes, that requires replacing the dust seals of the passenger service unit (PSU) panels of the overhead stowage compartment with new dust seals. The AD provides two options to accomplish this. Operators can either replace the seals all at once or remove the seals and repetitively clean and inspect the area to defer the installation for an interim period. The actions specified by this AD are intended to ensure replacement of dust seals of the lower PSU panel that may contribute to the spread of a fire when ignition occurs from electrical arcing of a failed light holder assembly, which could cause damage to adjacent structure and smoke emitting from the PSU panel into the passenger cabin. This action is intended to address the identified unsafe condition.